With her thirtieth birthday looming, Emma Harrison finds her biological clock clanging and the elusive knight in shining armor yet to appear. She’s running out of options, especially after her gay best friend backs out from being her sperm donor. Of course, there’s always a sperm bank, but Emma fears a donor mix-up might impregnate her with the spawn of Satan.

Resident company womanizer, Aidan Fitzgerald, is used to always getting what he wants, especially in the bedroom. When Emma spurns his advances at the company Christmas party, he's determined to have her no matter what it takes. After Aidan learns of Emma's predicament, he is quick to offer a proposition that will benefit them both. He will father Emma's child, but she must conceive it with him naturally. Not one for hook-ups or casual sex, Emma is reluctant to take him up on his offer, but his charm, coupled with her intense desire for motherhood, wins out.

Soon their baby-making sessions become more than just physical. Aidan can't seem to walk away from her while Emma begins to wonder if Aidan could be the one. But can Aidan leave his past behind to become the man Emma needs him to be?